diff --git a/openmp/runtime/cmake/config-ix.cmake b/openmp/runtime/cmake/config-ix.cmake
--- a/openmp/runtime/cmake/config-ix.cmake
+++ b/openmp/runtime/cmake/config-ix.cmake
@@ -175,6 +175,9 @@
       }
       int main() { int a = __kmp_umwait(0, 1000); return a; }")
   check_cxx_source_compiles("${source_code}" LIBOMP_HAVE_WAITPKG_INTRINSICS)
+  if (LIBOMP_HAVE_MRTM_FLAG)
+    set(CMAKE_REQUIRED_FLAGS -mrtm)
+  endif()
   set(source_code "// check for attribute rtm and rtm intrinsics
       #ifdef IMMINTRIN_H
       #include <immintrin.h>
@@ -191,6 +194,7 @@
       int main() { int a = __kmp_xbegin(); return a; }")
   check_cxx_source_compiles("${source_code}" LIBOMP_HAVE_RTM_INTRINSICS)
   set(CMAKE_REQUIRED_DEFINITIONS)
+  set(CMAKE_REQUIRED_FLAGS)
 endif()
 
 # Find perl executable